Obstetrics and Gynecology

A female patient in her first pregnancy presents to the obstetric triage unit at term ($39$ weeks of gestation). She reports the continuous leakage of clear vaginal fluid that began approximately $22$ hours prior to arrival. Currently, she is experiencing mild, irregular uterine contractions. Evaluation reveals a maternal core temperature of $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), a blood pressure of $110/70$ mm Hg, and a pulse of $115$/min. Fetal monitoring demonstrates a baseline heart rate of $175$/min with moderate variability and an absence of periodic decelerations. Abdominal examination is notable for diffuse fundal tenderness. Pelvic examination shows the cervix is $4$ cm dilated and $80\%$ effaced. What is the most appropriate next step in the management of this patient?

During normal pregnancy, profound maternal physiological adaptations occur that can mimic pathological disease states. Match each isolated clinical or laboratory finding observed in a healthy pregnant patient (Left) to its precise driving pathophysiologic mechanism (Right).

A 20-year-old woman comes to the clinic because of irregular menstrual periods and increased facial hair. Her menarche occurred at age 13. Her periods were initially regular but have become increasingly irregular over the past two years, now occurring every 3 to 4 months. She has also noticed coarse, dark hair growing on her chin and chest, and she has struggled with severe acne that has not responded to over-the-counter topical treatments. She takes no medications and has no other medical conditions. Vital signs show a blood pressure of 122/78 mmHg, pulse of 76/min, and a BMI of 31 kg/m². Physical examination reveals hirsutism on the face and chest and moderate inflammatory acne on the back. There is no clitoromegaly or deepening of the voice. Pelvic examination is unremarkable. A urine pregnancy test is negative. Initial laboratory studies show a normal serum thyroid-stimulating hormone (TSH) level and a normal serum prolactin level. Which of the following is the most appropriate next step in the evaluation of this patient?

A young patient with an intrauterine pregnancy confirmed by home testing presents for initial obstetric care. She is currently at 8 weeks gestation based on her last menstrual period. She has no chronic medical conditions. Throughout the course of a normal, low-risk pregnancy, arrange the following standard prenatal evaluations in the correct chronological sequence from earliest to latest.

During an ongoing labor induction for post-term pregnancy, a $31$-year-old nulliparous woman at $41$ weeks gestation is evaluated for abnormal fetal monitoring. She is receiving a continuous intravenous oxytocin infusion. Her most recent laboratory results demonstrate a hemoglobin concentration of $10.4\text{ g/dL}$ and a normal basic metabolic panel. On continuous electronic fetal monitoring, the baseline heart rate is $145\text{/min}$ with moderate variability. The tracing reveals symmetric, gradual decreases in the fetal heart rate that nadir after the peak of uterine contractions and return to baseline after the contractions end. Simultaneously, the tocodynamometer records $7$ contractions every $10$ minutes. In response, the clinical team stops the oxytocin infusion, alters her position to the left lateral decubitus, and provides an intravenous fluid bolus. Reassessment $15$ minutes later reveals ongoing uterine activity with $6$ contractions per $10$-minute period and persistence of the fetal heart rate decelerations. Her cervix is $4\text{ cm}$ dilated.

Which of the following is the most appropriate next step in the management of this patient?

A term patient in active labor reaches complete cervical dilation and begins the pushing phase. After several contractions, the fetal head emerges but then abruptly retracts against the vulva, and the fetal cheeks begin to bulge. Standard gentle downward traction does not yield delivery of the body. Arrange the following interventions in the correct sequential order for managing this clinical scenario, from initial response to maneuvers of last resort.

A $31$-year-old gravida $2$, para $1$ at $25$ weeks gestation presents to the clinic for a scheduled prenatal evaluation. She reports mild shortness of breath when walking up stairs and increased urinary frequency over the past few weeks, but otherwise feels well. Her first pregnancy was uncomplicated, resulting in a term vaginal delivery. Vital signs show a blood pressure of $110/68$ mm Hg, heart rate of $86$/min, and respiratory rate of $18$/min. Physical examination reveals a gravid uterus consistent with gestational age and trace bilateral pedal edema. Laboratory studies reveal the following:

Which of the following is the most appropriate next step in the management of this patient?

A 23-year-old primigravida at 18 weeks gestation presents to the clinic for a routine prenatal visit. She reports feeling well and has no complaints. Vital signs are within normal limits. A comprehensive metabolic panel is obtained as part of her evaluation. The results show a blood urea nitrogen (BUN) level of 7 mg/dL and a serum creatinine level of 0.4 mg/dL. Urinalysis reveals no protein or blood. Which of the following physiological adaptations of pregnancy is the most likely cause of these laboratory findings?

A 26-year-old G1P0 presents for a prenatal visit. According to her last menstrual period (LMP), she is at 19 weeks gestation. The patient reports having irregular menstrual cycles occurring every 35 to 45 days prior to conception. She did not establish prenatal care until this week, and a first-trimester ultrasound was not performed. On physical examination, her fundal height is palpable roughly midway between the pubic symphysis and the umbilicus.

Maternal serum quad screening is obtained. The laboratory calculates the multiples of the median (MoM) for her analyte levels based on the estimated gestational age of 19 weeks from her LMP. The results are as follows:

Maternal serum alpha-fetoprotein (MSAFP): $0.5$ MoM (Normal: $0.7 - 2.5$)
Unconjugated estriol: $0.6$ MoM (Normal: $> 0.8$)
Human chorionic gonadotropin (hCG): $2.4$ MoM (Normal: $< 2.0$)
Inhibin A: $2.2$ MoM (Normal: $< 2.0$)

Which of the following is the most appropriate next step in the management of this patient?

A 29-year-old primigravida presents to the obstetrics clinic to establish prenatal care. According to a recent dating ultrasound, she is at 9 weeks gestation. She has no significant past medical history and currently takes a daily prenatal vitamin. Her blood pressure is 112/68 mm Hg, heart rate is 82/min, and body mass index is 23 kg/m $^2$. Physical examination is unremarkable. The patient is eager to understand the upcoming milestones in her pregnancy and asks the physician to explain the precise timeline of routine testing she will undergo over the next several months.

Arrange the following routine prenatal screening tests and evaluations in the chronological order they should be offered or performed during this patient's uncomplicated pregnancy.

An expectant mother at $31$ weeks gestation visits her obstetric provider for a scheduled follow-up. Her pregnancy has progressed without complications, and she reports robust fetal movements. She recently had a comprehensive metabolic panel drawn for an independent life insurance policy application, which revealed an alkaline phosphatase level of $250$ U/L (reference range: $40$-$150$ U/L). Her aspartate aminotransferase, alanine aminotransferase, and total bilirubin levels are completely normal. She specifically denies any generalized pruritus, right upper quadrant abdominal pain, or nausea. Which of the following is the most appropriate next step in management?

Match each maternal clinical presentation occurring during the third trimester with the most accurate obstetric diagnosis.

A healthy 24-year-old nulliparous woman is admitted to the labor suite at 40 weeks gestation. She is in active labor with an epidural catheter in place for analgesia. Her blood pressure is 118/74 mm Hg and her heart rate is 84/min. Pelvic examination reveals a cervix that is 7 cm dilated and fully effaced, with the fetal vertex at -1 station. Thirty minutes ago, an amniotomy was performed to augment labor progression, yielding clear amniotic fluid. Currently, the continuous fetal heart rate monitor displays a baseline of 145/min with moderate variability. The tracing also demonstrates multiple abrupt drops in the fetal heart rate down to 85/min, lasting approximately 45 seconds before returning sharply to baseline. These drops vary in their timing relative to the onset of uterine contractions. The nursing staff has already repositioned the patient to the left lateral decubitus position and administered a bolus of intravenous lactated Ringer solution, but the heart rate pattern remains unchanged. Which of the following is the most appropriate next step in management?

A 28-year-old G2P1 presents to the clinic to establish prenatal care. She has a history of irregular menstrual cycles and is unsure of her last menstrual period. She will undergo serial transvaginal and transabdominal obstetric ultrasounds to confirm intrauterine pregnancy, verify gestational age, and assess early fetal development. Arrange the following normal sonographic landmarks in the typical chronological order of their initial appearance during a developing intrauterine pregnancy, from earliest to latest.

A $27$-year-old G1P0 at $35$ weeks gestation is evaluated in the obstetric triage unit for a $2$-day history of progressively worsening right upper quadrant pain, nausea, and profound fatigue. She reports normal fetal movement and denies any vaginal bleeding or leakage of fluid. Her temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $156/102$ mm Hg, and heart rate is $92$/min. Physical examination reveals tenderness to deep palpation in the right upper quadrant and $2+$ pitting edema of the bilateral lower extremities. Laboratory studies show:

A continuous fetal heart rate monitor shows a baseline of $145$/min, moderate variability, and frequent early decelerations coincident with mild, irregular uterine contractions. Which of the following is the most appropriate next step in management?

A 32-year-old woman, gravida 3, para 2, at 39 weeks gestation is admitted to the labor and delivery unit in spontaneous active labor. Her pregnancy is complicated by polyhydramnios. Her vital signs are within normal limits. Cervical examination reveals 5 cm dilation, 80% effacement, and the fetal presenting part at -2 station. Thirty minutes later, the patient experiences a spontaneous rupture of membranes with a large gush of clear fluid. The continuous electronic fetal heart rate monitor immediately shows a sudden, prolonged deceleration to 70/min that persists for 3 minutes. The nurse performs a sterile vaginal examination and palpates a pulsating, rope-like mass protruding through the cervical os ahead of the fetal presenting part. Which of the following is the most appropriate next step in the management of this patient?

Match each classic clinical presentation of an obstetric complication with its most likely diagnosis.

A primigravid patient is evaluated in the labor and delivery unit at 38 weeks gestation for active labor. She is currently 5 centimeters dilated and is receiving an intravenous oxytocin infusion for labor augmentation. Continuous electronic fetal monitoring displays a baseline heart rate of 145/min with moderate variability. During the observation period, the fetal heart rate tracing demonstrates recurrent, symmetric, gradual decreases in heart rate that consistently begin after the peak of the uterine contractions. The nadir of these decreases occurs after the contraction peak, and the heart rate slowly returns to baseline after the contraction has completely ended. Maternal vital signs are within normal limits. Which of the following is the most appropriate initial step in the management of this patient?

Match the following specific ultrasonographic and clinical findings in monochorionic twin gestations with their most accurate diagnosis.

During an initial prenatal evaluation at $10$ weeks of gestation, a nulliparous woman reports experiencing daily nausea and intermittent vomiting over the past three weeks. She notes a $1.5$-kg ($3.3$-lb) weight loss since her positive pregnancy test but is able to tolerate small, frequent meals. Her medical history is unremarkable, and she takes a daily prenatal vitamin. Vital signs demonstrate a pulse of $98$/min and a blood pressure of $108/66$ mm Hg. Physical examination reveals a normal, non-enlarged thyroid gland without palpable nodules. Cardiac auscultation shows a regular rhythm without murmurs.

Laboratory studies return the following results:

Which of the following mechanisms best explains this patient's specific combination of thyroid laboratory findings?